Tham khảo tài liệu 'teaching academic esl writing part 13', ngoại ngữ, toefl - ielts - toeic phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 108 CHAPTER 5 Irregular Plural Forms of Nouns. Other highly common nouns from the University Word List and Academic Word List that have irregular plural forms are axis crisis criteria emphasis focus hypothesis index matrix me-dia medium overseas parenthesis pendulum phenomenon radius series species strata thesis. All nouns that end in -is take the plural marker -es crises emphases hypotheses parentheses -ex ix endings become plural -ces indices matrices -um nouns take -a medium media stratum strata and -on endings have the plural form of -a criterion criteria phenomenon phenomena . Such nouns as overseas series and species have identical plural and singular forms one series several series one species many species . These nouns are not likely to be frequent in conversations and daily spoken interactions. For this reason they probably cannot be learned in the course of routine communications and activities for developing conversational fluency see chap. 1 . This may be one of the reasons that the vocabulary of even advanced and proficient L2 students does not include them. Although teachers may attempt to design activities and exercises to provide students practice with these nouns it is doubtful that many enjoyable tasks can be constructed with nouns such as axis crisis and hypothesis. Nonetheless it is essential for students to know the meaning pronunciation and spelling of these nouns at least to recognize them when they appear in academic reading and lectures. There are few better solutions to the dilemma of their learning beyond simple memorization and contextualized practice and use. The key to success in students vocabulary learning is the teacher s insistence that essential vocabulary nouns be used when they are needed. SINGULAR AND PLURAL NOUNS WITH DIFFERENT MEANINGS Many essential countable nouns such as business development difficulty failure industry injustice technology and truth have different meanings in singular and plural forms. When used in .
